One way to illustrate a story is with charts. All too often though misleading graphs are used to make an incorrect point.

A Verge story on Groupon shows how to get graphs right – clear, simple and tells the story of how the group buying service’s valuation soared and then plunged while it has never really been profitable.

The vertical axis is the key to getting a graph right, cutting off most of the y-axis’ range is an easy way to mislead people with graphs. In this case you can see just the extent of Groupon’s valuation, profit and loss over the company’s short but troubled history.

Since its inception, The Verge has been showing other sites how to tell stories online, their Scamworld story exposing the world of affiliate internet marketing sets the bar.

Using graphs well is another area where The Verge is showing the rest of the media – including newspapers – how to do things well.

For Groupon, things don’t look so good. As The Verge story points out, the company’s income largely tracked its workforce which grew from 126 at the start of 2010 to over 5,000 by April of 2011. Which illustrates how the business was tied into sales teams generating turnover.

The spectacular growth of Groupon and other copycat businesses couldn’t last and hasn’t. The challenge for Groupon’s managers is to now build a sustainable business.

For investors, those graphs of Groupon’s growth were a compelling story. Which is another reason why we all need to take care with what we think the charts tell us.